Judging by some recent events, the Zogenix executive team may want to reach for a painkiller. Over the past week, the drug maker suffered a pair of setbacks. First, Express Scripts , the nation’s largest pharmacy benefits manager, removed its Zohydro ER prescription painkiller from its national formulary, or list of medicines for which reimbursement is provided. Then, the chief commercial officer, Scott Shively, resigned to take another job. And now, the sales and marketing team is undergoing an internal review.